External hard drives consist of a hard disk inside a durable housing, and usually connect to a computer through a USB or Firewire cable. These devices provide a great way to back up data on your computer, transfer files from one computer to another, or just store additional files that won't fit on your computer's hard drive. There are several reasons you may want to wipe all the data from an external hard drive (in a process called "formatting"). You may want to remove clutter from the drive and start with a fresh volume, or you may want to remove any sensitive data before selling the hard drive to another person. Formatting a drive will also allow you to change the file system used by the drive to organize data. Learning how to wipe clean an external hard drive can help you accomplish these tasks with ease.

Steps

1

Back up any important data on the hard drive. If there is any data on the drive that you need to keep, make sure to save it on another volume (for example, your computer's hard drive) before formatting the external hard drive.

2

Format the external hard drive. Formatting the drive erases all of its data in a process designed to prepare the drive for use with a certain operating system and file system. The process is simple.

On a computer running Windows, right-click on the drive's icon and select "Format" from the context menu. Adjust the settings as desired, and then click "Start" and then "OK." When the drive is done being formatted, click "OK."

On a Mac, open the Disk Utility application by clicking on its icon in the Applications folder. Select your external hard drive in the left panel and then click the "Erase" button in the right panel (under the "Erase" tab). Click "OK" to format the drive.

Note that reformatting the external hard drive will not provide absolute protection for your sensitive files. Someone with advanced computer knowledge may be able to recover your data even after you reformat the drive. If security is a concern, make sure to take further steps to clean the drive.

3

Run a disk cleaning application on the external hard drive. If you want a more secure way to erase your data than reformatting, you can run a disk cleaning utility. These programs work by writing meaningless data to the hard drive, effectively overwriting your old data to make room for the new. 2 popular disk cleaning utilities are Drive Cleanser by Acronis and Darik's Boot and Nuke.

To wipe your external drive using these applications, install the software and open it. Select the external hard drive in the programs interface and erase its contents (note that this process usually takes a long time). Be very careful not to erase the data on your computer's built-in hard drive.

4

Physically destroy the hard drive. If complete security is a concern and you don't plan on ever using the hard drive again, you can take it apart and break the internal components. Most external hard drives have a housing that can be removed with a screwdriver. The interior components are delicate and can be effectively broken by covering them with a towel and striking them with a hammer. Before employing this method, however, consider donating your hard drive or recycling it at an electronics recycling center.